Cross reference is made to the following co-pending patent applications, each being assigned to the same assignee as the present invention and the teachings included herein by reference:
1. Field of the Invention
The present invention relates to wireless communications and more particularly to TDMA packet data.
2. Description of Related Art
Wireless communication systems under current development are often being designed to include enhanced capabilities to support the transmission of data. Wireless communication systems under current development are often being designed to include enhanced capabilities to support the transmission of data information. Wireless network communications for controlling data transfer typically are more complicated than wireless communications for controlling conversation.
Wireless data communication typically is more complicated than wireless voice communication since the data channel may provide both control and data transfer capabilities. Further, all data terminals share the resources of the data channel.
Accordingly, the multiplexing between control messages and data transfer messages requires greater control mechanisms than those ordinarily required for controlling conversation between individuals on the voice network.
Because of the multiplexing of control and data transfer on one channel, the data transfer may occupy the channel for extended periods of time limiting the control bandwidth.
There is a need, therefore, for communication networks and corresponding communication control protocols that need to be adapted to be responsive to new problems that are created as a result of new air interface resource allocation needs in order to improve network efficiencies.
Common message volume for data transfers are now often extended or larger in comparison to message sizes used to set up a conversation between two communication devices. Accordingly, the extended message volume can result in certain mobile stations capturing a communication control channel for longer periods of time. Under current technology, other mobile stations are not allowed to access the channel until the transmission is complete. In the current invention, however, an apparatus and a method is disclosed for interrupting the transmission of a particular control message to facilitate the intermittent transmissions of smaller messages thereby decreasing access delays for mobile stations and reducing the queuing delay in base stations and, accordingly, increasing network efficiencies.
More particularly, the Idle flag which has been previously used in control related communications between a base station and a mobile station to cause the mobile station to abort the current access attempt and/or to seek a new access opportunity has been functionally redefined to merely cause the mobile station to suspend communications on the channel but to not abort or seek an alternate channel for continuing communications. In the inventive system however, the Idle flag is used, in part, to suspend communications on a channel to allow another mobile station to use the channel. Accordingly, the Idle flag is used to allow any mobile station within the service area which is seeking an access opportunity to access the channel. An additional control flag is created which prompts a specific mobile station to start or continue a particular signal transmission. The Check flag will allow a particular mobile station identified by its Partial Echo to access or use the channel. Neither the Idle or Check flags cause the original channel owner to lose the channel. The existing IS-136 access protocol is modified to include processing capability for the redefined Idle flag as well as for the new Check flag.
An inventive method includes the step of changing or seeking new channels for communications whenever a first specified flag has been set and a specified period of time has elapsed since the flag was set or whenever a second specified flag has been set. More specifically, a data packet is transmitted in a first embodiment in the form of a burst whenever an Idle flag is set. In another embodiment, a burst is transmitted whenever a Check flag is set and a Partial Echo transmitted by the base station matches the identity of the mobile station. In another embodiment, a burst is transmitted if a Reserved flag is set and a Partial Echo transmitted by the base station matches the mobile station identity. In yet another embodiment, a burst is transmitted whenever the Reserved or the Check flags are set and the Partial Echo matches.